Visual adaptation photoelectric memristor based on oxide heterojunction and preparation method thereof

Abstract

The invention discloses a visual adaptation photoelectric memristor based on an oxide heterojunction and a preparation method of the visual adaptation photoelectric memristor. The visual adaptation photoelectric memristor comprises a bottom electrode layer, a NiO layer, an InGaZnO layer and a top electrode layer. According to the visual adaptation photoelectric memristor, through the photoelectric synergistic effect, when the illumination intensity changes, the resistance value of the photoelectric memristor can be adjusted according to the input light intensity, and the self-adaptation mechanism of a biological vision system is successfully simulated. The device has adjustable visual adaptation capability, the visual adaptation sensitivity can be adjusted by changing the stimulation intensity of ultraviolet light, the visual adaptation accuracy can be regulated by changing the stimulation frequency and stimulation number of the ultraviolet light, and simulation of controllable biological sensitivity and simulation of adjustable biological accuracy are achieved. And the response capability to complex environment change is improved, so that the system has a dynamic balance function similar to biological vision, and has a wide application prospect in the fields of intelligent sensing, neuromorphic calculation and artificial vision.

Description

Technical Field

[0001] The present invention relates to the field of vision adaptation and intelligent sensing technology, and in particular to a vision adaptation photoelectric memristor based on oxide heterojunction and a preparation method thereof. Background Art

[0002] With the development of technology, the next generation of artificial vision systems urgently need to have feedforward adaptation capabilities, that is, to achieve active adjustment of dynamically changing stimuli through information preprocessing. Visual adaptation is a fundamental process in biological systems, which enables organisms to adapt to changes in light intensity and maintain stable visual perception under various environmental conditions. This dynamic adjustment of sensory sensitivity is essential for the effective operation of the visual system. Simulating this behavior in artificial systems is a challenge and has aroused great interest in the fields of neuromorphic engineering and optoelectronics. Visually adaptive photoelectric memristors can adjust resistance according to light intensity, and their development provides great potential for creating neuromorphic systems that can process sensor information in real time. Photoelectric memristors with visual adaptation capabilities can simulate the adaptive mechanism of biological visual systems, bringing revolutionary innovations to the next generation of smart sensors, image processing, and neuromorphic computing.

[0003] Bionic visual adaptation is one of the key functions in artificial intelligence systems. Simulating and realizing biological visual adaptation mechanisms has become an important research direction. Although the technology has made some progress in the laboratory, photoelectric memristors are still in the exploratory stage in simulating visual adaptation, and there are many problems that need to be solved. In terms of material selection, some high-efficiency materials (such as perovskite and MoS2) are unstable under light or humidity conditions, and it is necessary to introduce a protective layer or optimize the material structure to improve its durability. Oxide materials have high chemical stability, good physical stability and excellent light stability, and are expected to play a greater potential in visual adaptation photoelectric memristors and promote their application and development in intelligent sensing and artificial vision systems. Summary of the invention

[0004] The purpose of the present invention is to solve the problem of instability of photoelectric materials in visual adaptation photoelectric memristors, and to provide a visual adaptation photoelectric memristor based on oxide heterojunction and a preparation method thereof.

[0005] A visually adaptive photoelectric memristor based on an oxide heterojunction, wherein the structure comprises, from bottom to top, a bottom electrode layer, an oxide heterojunction, and a top electrode layer;

[0006] The oxide heterojunction is composed of a NiO layer and an InGaZnO layer from bottom to top;

[0007] The bottom electrode layer is conductive glass;

[0008] The conductive glass is indium tin oxide ITO or fluorine-doped tin oxide FTO conductive glass;

[0009] The top electrode layer is: platinum, gold or tungsten;

[0010] The thickness of the top electrode layer is 15-25 nanometers; the thickness of the NiO layer is 40-60 nanometers; and the thickness of the InGaZnO layer is 120-150 nanometers.

[0011] A method for preparing a visually adaptive photoelectric memristor based on an oxide heterojunction, wherein a NiO layer and an InGaZnO layer are sequentially deposited on a bottom electrode layer by magnetron sputtering, atomic layer deposition or pulsed laser deposition; and a top electrode layer is deposited on the InGaZnO layer by thermal evaporation.

[0012] The bottom electrode layer is indium tin oxide (ITO) conductive glass, and the NiO layer is grown by magnetron sputtering;

[0013] Magnetron sputtering conditions: chamber background vacuum greater than 10 -4 Pa; NiO target purity is 99.99%; NiO target sputtering power is 60W; working atmosphere is pure argon; sputtering pressure is 0.6Pa; sputtering time is 10 minutes.

[0014] The IGZO layer is grown by magnetron sputtering; the magnetron sputtering conditions are: the chamber background vacuum is greater than 10 -4 Pa; IGZO target purity is 99.99%; sputtering power is 100W; working atmosphere is argon flow rate 11sccm, oxygen flow rate 1cssm; sputtering pressure is 0.6Pa; sputtering time is 20 minutes.

[0015] The visual adaptation photoelectric memristor of the present invention can simulate the adaptation mechanism of the biological visual system through the photoelectric synergy strategy. When the light intensity changes, the resistance value of the photoelectric memristor will be adjusted according to the input light intensity, so that it can achieve optimized power consumption management and information processing capabilities under different lighting conditions. The visual adaptation photoelectric memristor of the present invention has adjustable visual adaptation ability, the sensitivity of visual adaptation can be adjusted by changing the stimulation intensity of ultraviolet light, and the accuracy of visual adaptation can be regulated by changing the stimulation frequency and number of ultraviolet light, realizing the simulation of controllable biological sensitivity and adjustable biological accuracy. This adaptability can not only improve the device's responsiveness to complex environmental changes, but also enable the system to have a dynamic balance function similar to biological vision, reducing energy consumption and computational redundancy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a structural diagram of a visually adaptive photoelectric memristor based on oxide heterojunction of the present invention;

[0017] In the figure: 1, bottom electrode layer; 2, NiO layer; 3, InGaZnO layer; 4, top electrode.

[0018] Figure 2 Current response curve after applying UV light during current-time scanning test of visual adaptation photoelectric memristor;

[0019] Figure 3 The current-time scanning curves under different UV light stimulation intensities;

[0020] Figure 4 is the relationship between the sensitivity of visual adaptation and the intensity of ultraviolet light stimulation;

[0021] Figure 5 The current-time scanning curves under different UV light stimulation frequencies;

[0022] Figure 6 The relationship between the accuracy of visual adaptation and the frequency of UV light stimulation;

[0023] Figure 7 This is the relationship between the accuracy of visual adaptation and the number of ultraviolet light stimuli. DETAILED DESCRIPTION

[0024] Example 1

[0025] A visually adaptive photoelectric memristor based on oxide heterojunction and a preparation method thereof. Figure 1 , which is a schematic diagram of the photoelectric memristor ITO / NiO / IGZO / Au structure used in this embodiment, and the structure comprises a bottom electrode ITO, a NiO layer, an InGaZnO layer, and a top electrode Au from bottom to top.

[0026] The preparation method of the present invention has the following specific process:

[0027] Step 1: Use the purchased ITO conductive glass as the bottom electrode layer.

[0028] Specifically, the pre-treatment steps of the conductive glass are as follows: After cutting the indium tin oxide (ITO) substrate, place it in trichloroethylene, acetone, anhydrous ethanol and secondary deionized water for ultrasonic cleaning for 10 minutes, with an ultrasonic power of 70W to remove impurities such as oil on the surface of the substrate. After cleaning, use an air compressor to blow dry the surface of the indium tin oxide (ITO) substrate to facilitate the subsequent growth of the dielectric layer.

[0029] Step 2: grow the NiO layer by magnetron sputtering.

[0030] Specifically, the magnetron sputtering conditions are as follows: the chamber background vacuum is greater than 10 -4Pa; NiO target purity is 99.99%; NiO target sputtering power is 60W; working atmosphere is pure argon; sputtering pressure is 0.6Pa; sputtering time is 10 minutes;

[0031] Step 4: grow the IGZO layer by magnetron sputtering.

[0032] Specifically, the magnetron sputtering conditions are as follows: the chamber background vacuum is greater than 10 -4 Pa; IGZO target purity is 99.99%; sputtering power is 100W; working atmosphere is argon flow rate 11sccm, oxygen flow rate 1cssm; sputtering pressure is 0.6Pa; sputtering time is 20 minutes.

[0033] Step 5: Prepare the top electrode layer Au by thermal evaporation method.

[0034] Specifically, the thermal evaporation conditions are as follows: the chamber vacuum is greater than 10 -4 Pa; Au wire (0.1 g) evaporation material purity is 99.99%; heating current is 130 A;

[0035] The above photoelectric memristor was tested using a semiconductor parameter analyzer. During the test, the bottom electrode was connected to the negative pole of the power supply, the top electrode was connected to the positive pole of the power supply, an electrical signal was applied to the top electrode, the read voltage was 0.5V, and the optical modulation was achieved by a xenon light source with an ultraviolet light intensity of 0.1-0.5mW / cm 2 , the illumination time is 0.5-10s. Figure 2 As shown, when the photoelectric memristor is subjected to a current-time scanning test and ultraviolet light stimulation is applied, the current response of the device first increases rapidly, reaches a peak value, and then gradually decreases until it reaches a steady state, which is highly similar to the biological visual adaptation behavior. Figure 3 The current-time scanning curve of the photoelectric memristor under different UV light stimulation intensities. When the light intensity changes, the resistance value of the photoelectric memristor will be adjusted according to the input light intensity. Specifically, the response current of the device increases with the increase of UV light stimulation intensity. Figure 4 This is the relationship between the sensitivity of the device and the intensity of ultraviolet light stimulation. The sensitivity increases with the increase of light, realizing the simulation of controllable biological sensitivity. Figure 5 This is the current-time scanning curve of the photoelectric memristor under different UV light stimulation frequencies. The current curve of the device changes with the change of frequency. Figure 6 is the relationship between the accuracy of the device and the frequency of UV light stimulation. The accuracy increases with the increase of stimulation frequency. Figure 7The relationship between the accuracy of the device and the number of ultraviolet light stimuli is shown. The accuracy increases with the increase of the number of stimuli, realizing the simulation of adjustable biological accuracy. Therefore, the sensitivity of visual adaptation can be adjusted by changing the stimulation intensity of ultraviolet light, and the accuracy of visual adaptation can be adjusted by changing the stimulation frequency and number of ultraviolet light. The visual adaptation photoelectric memristor based on oxide heterojunction realizes the simulation of controllable biological sensitivity and adjustable biological accuracy.

[0036] The specific embodiments described above, the present invention develops a visual adaptation photoelectric memristor with light response and adaptation functions through photoelectric synergy. Compared with the prior art, the advantages of the present invention are that it realizes the simulation of controllable biological sensitivity and adjustable biological accuracy. The sensitivity of visual adaptation can be adjusted by changing the stimulation intensity of ultraviolet light, and the accuracy of visual adaptation can be adjusted by changing the stimulation frequency and number of ultraviolet light. By intelligently adjusting the response intensity, power consumption can be reduced under changing lighting conditions to avoid the waste of invalid energy. This feature is particularly important for sensor networks, Internet of Things devices and smart wearable devices that need to operate efficiently for a long time, so that it can find a balance between low power consumption and high efficiency, and can play an important role in the fields of smart visual sensors, automatic driving, monitoring equipment, etc.

Claims

1. A visually adaptive photoelectric memristor based on oxide heterojunction, characterized in that: The structure comprises, from bottom to top, a bottom electrode layer, an oxide heterojunction, and a top electrode layer; The oxide heterojunction comprises a NiO layer and an InGaZnO layer from bottom to top.

2. A visually adaptive photoelectric memristor based on oxide heterojunction according to claim 1, characterized in that: The bottom electrode layer is conductive glass.

3. The visually adaptive photoelectric memristor based on oxide heterojunction according to claim 2, characterized in that: The conductive glass is indium tin oxide ITO or fluorine-doped tin oxide FTO conductive glass.

4. The visually adaptive photoelectric memristor based on oxide heterojunction according to claim 3, characterized in that: The top electrode layer is made of platinum, gold or tungsten.

5. A visually adaptive photoelectric memristor based on oxide heterojunction according to claim 1, 2, 3 or 4, characterized in that: The thickness of the top electrode layer is 15-25 nanometers; the thickness of the NiO layer is 40-60 nanometers; and the thickness of the InGaZnO layer is 120-150 nanometers.

6. A method for preparing a visually adaptive photoelectric memristor based on oxide heterojunction, characterized in that: A NiO layer and an InGaZnO layer are sequentially deposited on the bottom electrode layer by magnetron sputtering, atomic layer deposition or pulsed laser deposition, and a top electrode layer is deposited on the InGaZnO layer by thermal evaporation.

7. A method for preparing a visually adaptive photoelectric memristor based on oxide heterojunction according to claim 6, characterized in that: The bottom electrode layer is indium tin oxide (ITO) conductive glass, and the NiO layer is grown by magnetron sputtering; Magnetron sputtering conditions: chamber background vacuum greater than 10 -4 Pa; NiO target purity is 99.99%; NiO target sputtering power is 60W; working atmosphere is pure argon; sputtering pressure is 0.6Pa; sputtering time is 10 minutes.

8. A method for preparing a visually adaptive photoelectric memristor based on oxide heterojunction according to claim 7, characterized in that: The InGaZnO layer was grown by magnetron sputtering; the conditions of magnetron sputtering were as follows: the background vacuum of the chamber was greater than 10 -4 Pa; IGZO target purity is 99.99%; sputtering power is 100W; working atmosphere is argon flow rate 11sccm, oxygen flow rate 1cssm; The sputtering pressure was 0.6 Pa and the sputtering time was 20 minutes.

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